Biomedical Engineering Reference
In-Depth Information
Fig. 6.4
The Ultimate HumanModel data set by cg Character, an artistic and anatomically accurate
human model [
38
]
Fig. 6.5
Muscle deformation by manipulating the control points of a NURBS surface
These geometrical skinning techniques consider the anatomy such that they can re-
produce muscle bulging, yet the deformation cannot be considered as realistic.
6.2.3.2 Segmented MRI and CT scans
3D representation of musculoskeletal models have been used extensively in ani-
mation to make better visualization and in biomechanics to study musculoskeletal
function in different clinical cases [
40
]. These representations can be generic or
subject-specific. Generic musculoskeletal models have some limitations. Most of the
software packages for biomechanical analysis of muscle function are based on bio-
mechanical studies of cadaveric specimens and use the musculoskeletal geometry of
a healthy, average-sized adult male with normal musculoskeletal geometry [
41
-
43
].
These models are useful for studying general trends in large populations. However, if
modeling results are to be used to plan surgical procedures, guide treatment decisions
and trial implant designs, they must take into account a subject's individual muscu-
loskeletal anatomy. Themusculoskeletal system is very intricate and large anatomical
variations exist among individuals. The different musculoskeletal geometry due to
size or pathology can also affect the accuracy of results derived from generic models.
Neuromuscular diseases, such as cerebral palsy, are often responsible for producing
